Conductor roll

ABSTRACT

A conductor roll adapted for conducting electroplating current from a metal strip to an external means and including a hollow steel body. The roll is produced by having the external surface thereof covered with an electrically conductive hardelectroplated layer, and having the internal surface thereof covered with a layer of copper plated thereon. The roll further has a copper roll shaft including a copper flange which is shrinkage-fitted in the aforesaid copper layer of the roll body by using a heating and cooling technique, so that the aforesaid flange intimately contacts the plated copper layer.

United States Patent Kanbayashi June 3, 1975 CONDUCTOR ROLL 3.6782267/1972 Hatagi 191/1 A M h k [75] Inventor i; lko Kanbayashl To PrimaryExaminer-M. Henson Wood, Jr.

p Assistant Examiner-D. W, Keen [73] Assignee: Yamato Kogyo KabushikiKaisha, Attorney, Agent, or FirmRobert E. Burns;

Japan Emmanuel J, Lobato; Bruce L. Adams [22] Filed: Jan. 3, 1974 4 2[57] ABSTRACT [21] Appl' 2 A conductor roll adapted for conductingelectroplating current from a metal strip to an external means [30]Foreign Application Priority Data and including a hollow steel body Theroll is pro- July 27, 1973 Japan 48434669 duced by having the externalsurface thereof covered with an electrically conductivehard-electroplated 5 C| H 191 20 25 layer, and having the internalsurface thereof covered 51 1m. 01 a. 801k 3/00 with a layer of pp Platedthereon The roll further [58] Field of Search .1 191/1 A; 29/1484 D,597, has a pp roll Shaft including a PP" flange which 29 10 123, 9; 204279 25 is shrinkage-fitted in the aforesaid copper layer of the rollbody by using a heating and cooling technique, so [56] References Citedthat the aforesaid flange intimately contacts the plated UNITED STATESPATENTS mppe layer- 2,958,742 11/1960 Palmer 1. 191/1 A 5 Claims 2Drawing Figures CONDUCTOR ROLL BACKGROUND OF THE INVENTION 1. Field ofthe Invention This invention relates to a conductor roll adapted for usein conducting electroplating current from a metal strip to an externalmeans, in a continuous electroplating of a metal strip.

2. Description of the Prior Art In the continuous electroplating of ametal strip, a conductor roll is maintained in contact with a metalstrip and driven at a peripheral speed corresponding to the travellingspeed of the metal strip. However, it is a common practice that anelectric current of a low voltage and high amperage such as of 18 voltsand 16,000 amperes, respectively, is introduced through a conductor rollfor electroplating. For such an application, a solid pure copper rollhaving a high electric conductivity has long found its use. However,such a copper roll has suffered from shortcomings in that, due to thelower hardness of the pure copper, the surface of a roll is susceptibleof damage and that the pure copper is costly.

Thus, for avoiding the aforesaid shortcomings in the conventional solidtype roll, there has been proposed a Japanese Patent Publication No.32130/70 published on Oct. I6, 1970 and issued to Hiroyuki Hatagi, etal., in which there was disclosed a roll of so called a dualconstruction consisting of an outer shell made of medium carbon steeladapted for preventing damage thereon and a pure copper core cylinderwhich is of good electric conductivity and fitted in the aforesaidshell. In this dual construction type cylindrical roll, the flange of acopper roll shaft is brazed to an inner copper roll. However, this meetsonly partial success in avoiding the aforesaid shortcomings and presentsa problem that, upon assembly, there is likely to be caused looseness orclearance, which gives adverese effect on electric conductivity, betweenthe steel outer roll and the copper inner roll, or distortion of theroll surfaces. This is because difficulties are encountered withaccurate or intimate fitting or lining of the copper roll in the outershell or because, despite different ex pansion coefficients of the twomaterials, the mating portions of the inner roll with the flange of theroll shaft is heated for brazing to a temperature of about 600C.

SUMMARY OF THE INVENTION It is accordingly an object of the presentinvention to provide a conductor roll which is provided with a hollowsteel roll body having a roll surface of a high strength and an innersurface of a good electric conductivity.

It is a further object of the invention to provide a conductor rollwhich is simple in construction and easy in manufacture.

It is a still further object of the present invention to provide aconductor roll which may save the material to be used and hence is notexpensive.

It has now been found that the foregoing and related objects can bereadily attained in a conductor roll of the invention, comprising ahollow steel roll body hav ing an outer surface covered with a chromiumplated layer or a nickel-plated layer and an inner surface thereofcovered with a copper layer electroplated thereon; a copper roll shaftincluding a flange shrinkage-fitted in said hollow body by using aheating and cooling technique in such manner that said flange contactssaid plated copper layer, said flange being coupled to said shaft; and asleeve, in which said roll shaft is titted and which has a flangecoupled to said roll body.

According to the present invention, a hollow roll body is coupled to aroll shaft, with the flange of the aforesaid roll shaft beingshrinkage-fitted in the aforesaid hollow roll body by using heating andcooling technique. For this purpose, the hollow roll body is heated tolOOC, while the flange of the roll shaft is cooled to -50C. Thereafterthe roll and shaft are brought back to a temperature range close to roomtemperature. As a result of the new construction there is no possiblityof peeling or separation of the copper layer from the aforesaid hollowroll body, nor blisters on the copper layer. Particularly, according tothe present invention, since the plated copper layer is formedintimately on the inner surface of the hollow roll body, there is nodanger of the aforesaid defects, experienced with the conventional dualconstruction type cylindrical roll, such as clearance between the outerand inner roll cylinders. Thus the invention has the result that theelectroplating current can be conducted in an improved manner from themetal strip via the copper layer to the roll shaft including the flangecoupled to said shaft.

The above mentioned and other objects and features of the invention willbecome apparent from the following detailed description taken inconjunction with the drawings which indicate embodiments of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinalcross-sectional view showing part of the new conductor roll, taken alongthe axial line of the roll; and

FIG. 2 is a modified detail view.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1, thereis shown a conductor roll of the invention, which comprises acylindrical hollow steel roll body 10. The roll body 10 has an innersurface which is copper-plated, thus providing a layer 2 of copperelectroplated on said inner surface and thereby uniformly intimatelybonded to all portions of said inner surface. With this layer 2, aflange 3 of a cop per roll shaft 4 is in contact. In other words, theflange 3 is fitted in the hollow roll body 10, so that the hollow body10 is electrically connected through copper layer 2 and flange 3 to thecopper roll shaft 4. A steel shaft sleeve 5 is provided on the rollshaft 4 and formed with a flange 6 which is coupled to the end portionof the hollow roll body 10. As shown, with this embodiment of theinvention, there is defined a chamber 7 between the flange 3 of the rollshaft 4 and the flange 6 of the sleeve 5. However, this chamber shouldnot be construed in a limitative sense, and hence the flange 6 maycontact the other flange 3. The hollow roll body 10 is fitted on theflange 3 of the roll shaft 4 by using a shrinkage-fitting technique byresorting to heating and cooling operations. For instance, the roll body10 is heated to C, while the roll shaft 4 is cooled to -50C.Alternatively, the hollow roll body 10 may be welded to the flange 6 ofthe shaft sleeve 5. Still alternatively, the shrinkage-fitting techniquemay be used for coupling the flange 6 to the hollow body 10.

Hard electroplating, such as for instance, hard chromium plating ornickel plating may be applied to the outer surface 8 of the roll body 10and that of the shaft sleeve 5, including the outer surface of theflange 6, so that a hard, metallic, electroplated layer 9 may protectthe roll body 10 from damage.

The sleeve is formed with a bearing portion 12 which rotatably supportsthe roll body in cooperation with another bearing portion (not shown).

On the other hand. an electric conductor ring 13, coupled with lock-nutsl4 and 15, is affixed on the end portion of the roll shaft 4, wherebyelectric current is introduced from the roll shaft 4 through a brush(not shown) in contact with the electric conductor ring 13 to externalmeans. The roll shaft 4 is adapted to rotate with the shaft sleeve 5.The roll shaft 4 may be welded to the sleeve 5.

There is defined a cooling-water passage 16 through the roll shaft 4along the axial line thereof, with the exits of passage 16 being open toa cavity 17 in body 10, communicating with chamber 7 through apertues inpiston 3. it is needless to mention that the supply of cooling waterthrough the aforesaid passage 16 may absorb joule heat generated in theroll body 10. The right hand portion of the conductor roll is not shownin the drawing, but its construction is identical to that of theleft-hand portion which is shown. In addition, the drive means is notshown in the drawing, because it is well known to those skilled in theart.

Turning now to FIG. 2, there is shown a small part of the conductor rollaccording to the present invention, which is somewhat different inconstruction from that shown in FlG. 1. FIG. 2 illustrates the portionof roll body 10 coupled to flange 3 of the roll shaft 4. As is clearfrom the drawing, there is applied a silver layer 18 between the copperlayer 2 electroplated on the roll body 10 and the copper flange 3. Thesilver layer 18 is formed on the edge surfaces of 3. As a result, thecontact of the flange 3 by electroplating the silver layer on this edgesurface through the silver layer 18 with the roll body 10 having aplated copper layer thereon re duces contact-resistance therebetween,thereby improving electric conductivity thereof.

The conductor roll according to the present invention may readily bemanufactured. More particularly, after the plated copper layer 2 hasbeen applied on the inner surface of the hollow roll body 10, the flange3 of roll shaft 4 is shrinkage-fitted in the roll body 10 by usingheating and cooling fitting technique. Then, the shaft sleeve 5 isfitted on the roll shaft 4 by introducing the sleeve from the endportion of the shaft onto the shaft. Thereafter the flange 6 thereof isrigidly coupled to the end portion of the hollow roll body 10.Thereafter, the outer surface of hollow roll body 10 is machined forcenteralignment. Upon completion of such operations, hard chromiumplating 9 is applied to the outer surface of roll body 10 as well as tothe surface of shaft sleeve 5, at the same time.

As is apparent from the foregoing description. plated copper layer 2 isapplied on the inner surface of steel roll 10, while the flange 3 ofcopper roll shaft is shrink age-fitted in roll body 10 by using aheating and cooling technique so that the flange 3 contacts the platedcop per layer 2. As a result. there is no possiblity of the platedcopper layer being peeled from hollow roll body 10. This plated copperlayer 2 tightly adheres on the one hand to the roll body 10, and on theother hand to the flange 3 of roll shaft 4. This in turn ensureselectric conductivity as high as that of the conventional solid typeroll, while the material to be used therefor may be materially reduced.In addition to this, the conductor roll of the invention may avoiddifficulties and defects in electric conductivity such as areexperienced with conventional dual-construction type cylindrical rolls.

It will be understood that the above description is merely illustrativeof preferred embodiments of the in vention. Additional modifications andimprovements utilizing the discoveries of the present invention can bereadily anticipated by those skilled in the art from the presentdisclosure, and such modifications and improvements may fairly bepresumed to be within the scope and purview of the invention as definedby the claims that follow.

What is claimed is:

1. A conductor roll for conducting electrical plating current,comprising:

a hollow steel roll body having an inner surface and an outer surface;

a hard metallic layer covering said outer surface; a

copper layer plated on said inner surface;

a copper shaft having a copper flange integrally connected thereto,which flange includes a silver layer in contact with the copper layer ofsaid roll body to mount the flange of the shaft in said hollow body withfirm electric contact between said copper and silver layers and saidcopper flange; and

an electric conductor ring affixed to said shaft externally of said rollbody.

2. In a conductor roll for conducting electroplating current:

a hollow steel roll body having an inner surface and an outer surface;

a hard metallic layer on said outer surface;

a layer of copper plated on said inner surface; and

copper roll shaft means fitted into said layer of copper to intimatelycontact said layerv 3. In a roll according to claim 2, a copper flangeintegrally connected to said shaft means and shrink-fitted to said layerof copper.

4. In the manufacture of a conductor roll for conducting dense electriccurrents:

making a hollow steel roll body with an inner surface and an outersurface, both cylindrically formed;

depositing a hard metallic layer on said outer surface;

electroplating a layer of copper on said inner surface; and fittingcopper roll shaft means into said layer of copper to intimately contactsaid layer.

5. ln manufacture according to claim 4, shrink-fitting said layer ofcopper to said copper roll shaft means.

1. A conductor roll for conducting electrical plating current,comprising: a hollow steel roll body having an inner surface and anouter surface; a hard metallic layer covering said outer surface; acopper layer plated on said inner surface; a copper shaft having acopper flange integrally connected thereto, which flange includes asilver layer in contact with the copper layer of said roll body to mountthe flange of the shaft in said hollow body with firm electric contactbetween said copper and silver layers and said copper flange; and anelectric conductor ring affixed to said shaft externally of said rollbody.
 1. A CONDUCTOR ROLL FOR CONDUCTING ELECTRICAL PLATING CURRENT,COMPRISING: A HOLLOW STEEL ROLL BODY HAVING AN INNER SURFACE AND ANOUTER SURFACE, A HARD METALLIC LAYER COVERING SAID OUTER SURFACE, ACOPPER LAYER PLATED ON SAID INNER SURFACE, A COPPER SHAFT HAVING ACOPPER FLANGE INTEGRALLY CONNECTED THERETO, WHICH FLANGE INCLUDES ASILVER LAYER IN CONTACT WITH THE COPPER LAYER OF SAID ROLL BODY TO MOUNTTHE FLANGE OF THE SHAFT IN SAID HOLLOW BODY WITH FIRM ELECTRIC CONTACTBETWEEN SAID COPPER AND SILVER LAYERS AND SAID COPPER FLANGE, AND
 2. Ina conductor roll for conducting electroplating current: a hollow steelroll body having an inner surface and an outer surface; a hard metalliclayer on said outer surface; a layer of copper plated on said innersurface; and copper roll shaft means fitted into said layer of copper tointimately contact said layer.
 3. In a roll according to claim 2, acopper flange integrally connected to said shaft means and shrink-fittedto said layer of copper.
 4. In the manufacture of a conductor roll forconducting dense electric currents: making a hollow steel roll body withan inner surface and an outer surface, both cylindrically formed;depositing a hard metallic layer on said outer surface; electroplating alayer of copper on said inner surface; and fitting copper roll shaftmeans into said layer of copper to intimately contact said layer.